Paraccocidioidomycosis
is the most frequently found endemic systemic mycosis in Brazil. No symptoms
are observed in the early phases of the disease. As the disease progresses, the
patient may present disseminated involvement, but bone involvement is extremely
rare. The present report is aimed at evaluating bone changes found on imaging
studies in a patient with osteomyelitis of the wrist as a result of
disseminated paracoccidioidomycosis.

Keywords: Paracoccidioidomycosis; Endemic mycosis; Osteomyelitis.

INTRODUCTION

Paracoccidioidomycosis is the most common endemic systemic
mycosis in Latin America(1,2). Such condition is acquired by
inhalation of infected particles which reach the lungs, developing primary
infection. In the early stages of the disease, the patient does not develop any
symptom or otherwise present subtle and nonspecific symptoms. As the disease
progresses, the patient presents severe involvement of several organs such as
skin, mucosas, lungs and bones. Such an infection may progress with
dissemination, but the disseminated presentation occurs in only 35% of cases(3).

The present report is aimed at evaluating bone changes
observed on imaging studies of a patient with osteomyelitis of the wrist
secondary to disseminated paracoccidioidomycosis, as a contribution to the
early diagnosis and treatment of this disabling disease.

CASE REPORT

A male, 59-year old patient who as agricultural worker and
with a long history of smoking attended an emergency unit in the city of
Vitória, ES, Brazil, reporting progressive dyspnea for three months, ulcerative
lesions on his skin and mucosas in association with pain and soft tissue
enlargement in his right wrist, with serosanguineous secretion. Findings at
physical examination included cervical and axillary lymph nodes enlargement,
ulcerative lesions on the skin of his dorsal region and oral mucosa, besides a significant
increase in volume of his right wrist.

Chest radiography demonstrated diffuse and confluent
opacities in the middle thirds of the pulmonary fields and opacities
corresponding to fibrotic scars in the lung bases. Radiography of the right
wrist demonstrated a subtle decrease in the bone density of the distal ulna
(Figure 1A).

Considering the radiographic findings, the patient was
treated with antibiotics and referred to the center of infecto-parasitic
diseases at Hospital Universitário Cassiano Antônio de Moraes. One month after
the treatment, new radiographic images of the wrist and high resolution
computed tomography (HRCT) of the chest were acquired in addition to fungal
serology and cytology of the wrist secretion. The cytology revealed the presence
of a high number of fungi compatible with Paracoccidioides brasiliensis.

Radiography of the right wrist demonstrated a lytic area in
the distal ulna (Figures 1B and 1C). The patient was submitted to magnetic
resonance imaging of the wrist, which demonstrated a significant involvement of
the bone marrow in the distal ulna, development of bone abscess and fistulous
trajectory, with involvement of the muscle and adjacent subcutaneous tissues,
with intense contrast-enhancement (Figure 2). At chest HRCT multiple
consolidations were observed in the middle and lower thirds of the lungs,
besides septal thickening, cavitating nodules and bronchial walls thickening
(Figure 3). Technetium and gallium scintigraphy was performed, confirming the
presence of active disease in the lungs and right wrist (Figure 4). Contrast
uptake was not observed in other bones or in the central nervous system.

The patient was admitted and initially treated with
Amphotericin B. After improvement of the respiratory symptoms and decrease in
volume of soft tissue components in his right wrist, the patient was discharged
with sulfamethoxazole-trimetro­pim, remaining under regular follow-up on an
outpatient basis.

DISCUSSION

Paracoccidioidomycosis affects primarily adult individuals in
their most productive phase, causing high social and economic impact. More than
90% of cases occur in male individuals(1,4), representing a
relevant public health problem because of its high disabling potential and high
mortality in cases of disseminated disease(4,5). Accurate
epidemiological data on the disease are not available in Brazil, since
Brazilian regulations do not require mandatory notification(6).

Paracoccidioidomycosis may manifest in several organs,
particularly in lungs, skin, mucosas and lymph nodes. Lungs are most commonly
affected(7), with radiographic changes in 60% of acute cases
and in up to 80% of chronic cases(8). Small opacities
constitute the most common pulmonary findings, generally with bilateral and
symmetric distribution of the lesions(4). Bones involvement
is extremely rare(3,911).

The typical finding is a well-defined lytic area, either with
or without a sclerotic halo that may be observed in any bone, either with or
without involvement of soft tissues. The disease is generally multifocal.
Differential diagnoses include other infectious diseases such as chronic
bacterial osteomyelitis, tuberculosis and primary or metastatic tumors such as
lymphoma and osteosarcoma.

The disease location is determined by hematogenous
dissemination. It was first described by Pereira and Vianna in 1911, in a case
with multiple bone lesions affecting the sternum, ribs, skull, tibia,
sternoclavicular joint and shoulder. Few cases of single bone involvement are
reported in the literature.

In many cases, osteomyelitis secondary to
paracoccidioidomycosis is a late diagnosis, resulting in high morbidity and
mortality.